Despite police refusing to acknowledge that they had any warning of the bombing attack on the Boston Marathon, eyewitness Ali Stevenson says authorities “must have known” of a threat because they announced a drill beforehand and had spotters on the roof at the start of the race.

Stevenson has gone into further detail about what he experienced in the morning at the start of the race, when participants in the marathon were told by police to stay calm as loudspeakers announced a bomb drill.

“At the starting line this morning, they had bomb sniffing dogs and the bomb squad out there,” he said. “They kept announcing to runners not to be alarmed, that they were running a training exercise,” Stevenson told AL.com.

However, during a press conference, Boston police told Infowars reporter Dan Bidondi that there was “no specific intelligence” regarding an attack and that no drills took place besides the usual precautions taken for a big event.

“They kept making announcements saying to the participants ‘do not worry, this is just a training exercise’” said Stevenson, who is the University of Mobile's Cross Country Coach.

“Evidently, I don’t believe they were just having a training exercise, they must have known,” Stevenson told Local15 News. “They must have had some sort of threat or suspicion called in,” adding that spotters were stationed on roofs of buildings and that bomb sniffing dogs were going up and down the finish line.

Stevenson said the level of security he witnessed was unlike anything he had experienced as a marathon runner before in major cities such as Chicago, Washington D.C., and London.

Photographic evidence confirms Stevenson’s claim that there were spotters on the roof before the bombs exploded.

As the Daily Mail reports, “A picture posted on Twitter shows an individual walking on the roof directly overlooking one of the blasts at the Boston Marathon.”

The fact that this individual is in such close proximity to the blast clearly suggests that he is either one of the perpetrators behind the attack or a police officer detailed with carrying out surveillance duties as part of the bomb drill.

Mike Adams explains, other inconsistencies in the official narrative also clearly suggest that the blasts were not unexpected.

“It is impossible for a bomb squad to have located, analyzed, rigged and detonated the third bomb in under an hour, especially when it was located one mile away, at the Kennedy Presidential Library,” he writes. “The Boston bomb squad clearly had advanced notice of the presence of the bombs at the marathon, and they also had advanced notice of the location of the bomb at the Kennedy Presidential Library. “
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Paul Joseph Watson is the editor and writer for Infowars.com and Prison Planet.com. He is the author of Order Out Of Chaos. Watson is also a host for Infowars Nightly News.